Abstract: Method of electrolytic drilling of a fluid metering orifice through a metal substrate including the step of terminating electrolytic current flow when the volume of the electrolyte stream impinging on the substrate correlates to the desired flow of the fluid through the orifice.

Abstract: A pair of outer conducting members on the outside of a windshield are separated by a long common insulating border defining a border resistance in parallel with a first capacitance. Each of the outer conducting members is capacitively coupled through a layer of the windshield to an inner conducting member to form coupling capacitances in series with the combination of the border resistance and first capacitance. The preceding elements form a timing circuit for an oscillator, the timing circuit having an equivalent capacitance varying with the border resistance. When water droplets bridge the border of the outer conducting members, the border resistance decreases from infinity to change the equivalent capacitance of the timing circuit and thus the frequency of the oscillator circuit; and this change is detected to modify wiper operation.

Abstract: A gas sensing apparatus suitable for repeatedly sensing the partial pressure of a selected gas in a gaseous mixture is accomplished by employing optical detecting means. A sensing material having a light reflective surface reversibly reacts with a sensed gas in accordance with a temperature-sensed gas partial pressure relationship to cause a predictable change in reflectivity of the light reflective surface. The chemical reaction between the sensing material and sensed gas is reversible, therefore allowing quick, precise and repetitive sensed gas partial pressure determinations.

Abstract: Rapid response, highly precise determinations of oxygen partial pressures in internal combustion engines operating with lean air/fuel mixtures are accomplished by using a thin film internal reference, solid electrolyte electrochemical type oxygen sensor comprising laterally disposed galvanic sense and pump cells on a single planar substrate, and an internal reference gas chamber provided by a cap. A cerium dioxide, thin film electrode on the galvanic pump cell provides an oxygen reservoir for the internal reference gas chamber.

Abstract: A precipitation sensor for detecting when a predetermined fraction of the sensor area is covered with water drops comprises an insulating substrate, a pair of spaced electrodes of conductive material on the substrate, and an array of conductive spots on the substrate between the electrodes, the spots being arranged to define an open circuit between the electrodes when the substrate is dry and a closed circuit when at least some of the spots are bridged by water drops. This sensor uses the physical principle of percolation to respond accurately to small amounts of precipitation and is preferably integrated in the wipe area of a windshield surface and is incorporated in the wiper control system.

Abstract: A method of producing high quality stoichiometric thin films of vanadium dioxide by reactive evaporation utilizes an electron beam to evaporate a source of vanadium in a controlled, low pressure oxygen gas environment with the film being deposited at a predetermined rate onto a substrate which is heated to and maintained at a predetermined temperature above 500.degree. C.